Name

       isnum - Return code telling whether the input string is numerical

Synopsis

       isnum string

Description

       isnum  is a utility for identifying and classifying an input string.  <B>isnum</B> returns
       an integer code depending on how it identifies the input number: 0: string is not any sort
       of  number  1:  String  is  an integer 2: String is a floating point number 3: String is a
       hh:mm:ss.ss time 4: String is a yyyy-mm-dd date

Author

       Jessica Mink, SAO (jmink@cfa.harvard.edu)